The preparation of 3-amino-3-deoxy-1,2-O-isopropylidene-α-L-erythrofuranose, 3-amino-3-deoxy-1,2-O-isopropylidene-β-D-threofuranose and their derivatives

The title amino derivatives VI and XIV were prepared by nucleophilic substitution of p-toluenesulfonyl derivatives II and XVII with sodium azide or hydrazine and subsequent reduction. Nucleophilic substitution of compounds II and XVII with sodium benzoate was also investigated. The 1H NMR spectra of the substances prepared are discussed.

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Synthesis and Antituberculotic Activity of Some Substituted 3-Arylamino-5-cyano-2-pyrazinecarboxamides

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19951236 ◽

1995 ◽

Vol 60 (7) ◽

pp. 1236-1241 ◽

Cited By ~ 7

Author(s):

Martin Doležal ◽

Jiří Hartl ◽

Antonín Lyčka ◽

Vladimír Buchta ◽

Želmíra Odlerová

Keyword(s):

Nucleophilic Substitution ◽

Elemental Analysis ◽

Nmr Spectra ◽

Substituted Anilines ◽

H Nmr

Nucleophilic substitution of 3-chloro-5-cyano-2-pyrazinecarboxamide by substituted anilines afforded substituted 3-arylamino-5-cyano-2-pyrazinecarboxamides I-X. The structures of compounds were confirmed by elemental analysis, UV, IR and 1H NMR spectra. The assessment of in vitro antimycotic and antimycobacterial activities of the compounds was carried out. The highest antituberculotic activity against M. tuberculosis in this series was shown by 3-anilino- 5-cyano-2-pyrazinecarboxamide (I), whose efficacy was the same as that of pyrazinecarboxamide.

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Preparation of pyridinium salts of 2-furane derivatives

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19842485 ◽

1984 ◽

Vol 49 (11) ◽

pp. 2485-2491 ◽

Cited By ~ 1

Author(s):

Miroslav Kríž ◽

Jaroslav Kováč ◽

Vladimír Mlynárik

Keyword(s):

Nucleophilic Substitution ◽

Substitution Reaction ◽

Nmr Spectra ◽

Nucleophilic Substitution Reaction ◽

Pyridinium Salts ◽

H Nmr ◽

C Nmr

Pyridinium salts have been prepared by nucleophilic substitution reaction of 5-halogeno-2-furane derivatives with pyridine and its 3- and 4-substituted derivatives, where R = 3-methyl, 3-ethyl, 3-amino, 3-methoxycarbonyl, 3-aminocarbonyl, 4-amino, 4-aminocarbonyl, 4-phenoxy, and 3,4-dimethyl, and structure of the derivatives prepared has been confirmed by their 1H NMR and 13C NMR spectra.

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1,4-Bis(p-pentazolylphenyl)butan, 1-p-Azidophenyl-4-p-pentazolylphenyl- butan und 1,4-Bis(p-azidophenyl)butan / 1,4-Bis(p-pentazolylphenyl)butane, 1-p-Azidophenyl-4-p-pentazolylphenyl-butane and 1,4-Bis(p-azidophenyl)butane

Zeitschrift für Naturforschung B ◽

10.1515/znb-2004-0614 ◽

2004 ◽

Vol 59 (6) ◽

pp. 716-720 ◽

Cited By ~ 1

Author(s):

Frank Biesemeier ◽

Klaus Harms ◽

Ulrich Müller

Keyword(s):

Low Temperature ◽

Sodium Azide ◽

Rate Constants ◽

Nmr Spectra ◽

Room Temperature ◽

Fine Powder ◽

Space Group ◽

H Nmr ◽

Diazonium Ions ◽

C Nmr

1,4-Bis(p-pentazolylphenyl)butane (1), 1-p-azidophenyl-4-p-pentazolylphenyl-butane (2) and 1,4-bis(p-azidophenyl)butane (3) were obtained by the reaction of 1,4-diphenylbutane-4’,4”- bis(diazonium) ions with sodium azide in methanol at −50 °C. In the 1H and 13C NMR spectra the three compounds can be distinguished unequivocally. At −50 °C a mixture with a composition 1:2:3 of 10:30:60 was obtained. By recrystallization first from dichloromethane/methanol and then from dichloromethane/petroleum ether the pentazole components were enriched to a composition ratio of 21:62:17. The rate constants of the decompositions 1→2 and 2→3 at 0 °C were determined from the variation of the 1H NMR intensities. At room temperature all of the material is converted to 3. 3 crystallizes in two monoclinic modifications. At −70 °C a modification 3-LT having space group P21/c (a = 950.8, b = 1192.6, c = 701.3 pm, β = 92.55°, Z = 2; R = 0.075) was obtained. The modification crystallizing at room temperature (3-HT) has space group I2/a (a = 1514.5, b = 498.1, c = 2027.9 pm, β = 92.73°, Z = 4; R = 0.040). Whereas both modifications consist of nearly identical molecules, their packings are quite different. When the low temperature modification is warmed to room temperature, its crystals jump like flees and are disrupted to a fine powder.

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Study of Amino-Imino Tautomerism in Derivatives of 2-, 4- and 6-Aminonicotinic Acid

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19942057 ◽

1994 ◽

Vol 59 (9) ◽

pp. 2057-2068 ◽

Cited By ~ 7

Author(s):

Svatava Smrčková ◽

Kristina Juricová ◽

Viktor Prutianov

Keyword(s):

Ir Spectroscopy ◽

Hydrogen Bonds ◽

Nmr Spectra ◽

Chemical Shifts ◽

Amino Derivative ◽

Ionic Character ◽

H Nmr ◽

Amino Derivatives ◽

Derivatives Of ◽

C Nmr

13C NMR spectra of p-nitrobenzoyl 2-, 4-, and 6-aminopyridine-3-carboxylates, their hydrochlorides, trifluoroacetates and 1-benzyl derivatives were studied. As found from the chemical shifts of pyridine carbon atoms C-2, C-4 and C-6, the free bases exist in the amino form whereas hydrochlorides and 1-substituted pyridinium derivatives in the imino form. Trifluoroacetates of the 2- and 6-amino derivatives have structure similar to that of amidiniumcarboxylates (parallel hydrogen bonds and partially ionic character) whereas trifluoroacetate of the 4-amino derivative is structurally close to the corresponding hydrochloride. The found structures were confirmed by 1H NMR and IR spectroscopy.

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Reactions of ethyl 4-bromo-3-(2-furyl)-2-butenoate with nitrogen nucleophiles

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19811513 ◽

1981 ◽

Vol 46 (6) ◽

pp. 1513-1517 ◽

Cited By ~ 1

Author(s):

Katarína Špirková ◽

Jaroslav Kováč ◽

Ivan Horsák ◽

Miloslava Dandárová

Keyword(s):

Nucleophilic Substitution ◽

Nmr Spectra ◽

Substitution Reactions ◽

Nucleophilic Substitution Reactions ◽

H Nmr ◽

Nitrogen Nucleophiles

Nucleophilic substitution reactions of ethyl 4-bromo-3-(2-furyl)-2-butenoate with nitrogen nucleophiles are described. UV, IR, and 1H NMR spectra of the prepared substances have been interpreted.

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Conformational structure of ethylene glycol dibenzoate. Vibrational and NMR spectra

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19811913 ◽

1981 ◽

Vol 46 (8) ◽

pp. 1913-1929 ◽

Cited By ~ 3

Author(s):

Bohdan Schneider ◽

Pavel Sedláček ◽

Jan Štokr ◽

Danica Doskočilová ◽

Jan Lövy

Keyword(s):

Ethylene Glycol ◽

Vibrational Spectra ◽

Nmr Spectra ◽

Coupling Constants ◽

Conformational Structure ◽

Infrared And Raman Spectra ◽

H Nmr ◽

Liquid States ◽

Crystalline Forms ◽

C Nmr

It was found that three crystalline forms of ethylene glycol dibenzoate can be prepared. Infrared and Raman spectra of these three forms, as well as of the glassy and liquid states, were measured. From 3JHH coupling constants obtained by analysis of the 13C satellite band of the -CH2- group in 1H NMR spectra, and from the 3JCH coupling constants of the -CO.O.CH2- fragment obtained by analysis of the carbonyl band in 13C NMR spectra it was found that in the liquid state the -CH2-CH2- group exists predominantly in the gauche conformational structure, and the bonds C-O-C-C assume predominantly a trans orientation. The results of the analysis of NMR and vibrational spectra were used for the structural interpretation of conformationally sensitive bands in vibrational spectra of ethylene glycol dibenzoate.

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Preparation and absolute configuration at C(20) of 21-nor-5α-chol-22-en-24→20-olide derivatives

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19810917 ◽

1981 ◽

Vol 46 (4) ◽

pp. 917-925 ◽

Cited By ~ 2

Author(s):

Vladimír Pouzar ◽

Miroslav Havel

Keyword(s):

Absolute Configuration ◽

Nmr Spectra ◽

Lithium Salt ◽

H Nmr ◽

Chemical Correlation ◽

Unsaturated Lactones

Reaction of the aldehyde I with the lithium salt of 1-(2-tetrahydropyranyloxy)-2-propyne yielded the compounds II and IV. From the compound II the lactone XII was prepared via the intermediates III and X, the lactone XVIII was prepared from the substance IV via the intermediates V and XVI. The unsaturated lactones XII and XVIII were also prepared by sulfenylation and dehydrosulfenylation of the saturated lactones XIII and XIX. Based on chemical correlation and 1H-NMR spectra analyses of the compounds II and IV, the lactone XII was assigned the 20R-configuration whereas the lactone XVIII was allotted the 20S-configuration.

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New type of addition to 5-substituted 4-arylidene-2-(4,5-dihydrofurfurylidene)-N,N-dimethyliminium bisperchlorates. Preparation of 4-substituted 5-(N,N-dimethylamino)-2-furancarbaldehydes

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19860573 ◽

1986 ◽

Vol 51 (3) ◽

pp. 573-580 ◽

Cited By ~ 3

Author(s):

Tibor Gracza ◽

Zdeněk Arnold ◽

Jaroslav Kováč

Keyword(s):

Nmr Spectra ◽

Addition Reaction ◽

H Nmr ◽

Organic Bases ◽

New Type

4-Arilidene-5-(N,N-dimethyliminium)-2-(4,5-dihydrofurfurylidene)-N,N-dimethyliminium bisperchlorate I undergoes a 1,4-addition reaction with organic bases under re-formation of the furan nucleus; this behaviour has been utilized in the preparation of new 4-substituted 5-(N,N-dimethylamino)-2-furancarbaldehydes II, III. The structure of the prepared compounds has been confirmed by 13C and 1H NMR spectra.

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Preparation, properties and structure of some intermediate nido- and arachno-monocarbaboranes

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19812345 ◽

1981 ◽

Vol 46 (10) ◽

pp. 2345-2353 ◽

Cited By ~ 33

Author(s):

Karel Baše ◽

Bohumil Štíbr ◽

Jiří Dolanský ◽

Josef Duben

Keyword(s):

Transition Metal ◽

Metal Complexes ◽

Transition Metal Complexes ◽

Nmr Spectra ◽

Liquid Ammonia ◽

X Ray Diffraction ◽

X Ray ◽

H Nmr ◽

Starting Compound

The 6-N(CH3)3-6-CB9H11 carbaborane reacts with sodium in liquid ammonia with the formation of 6-CB9H12- which was used as a starting compound for preparing the 4-CB8H14, 9-L-6-CB9H13 (L = (CH3)2S, CH3CN and P(C6H5)3), 1-(η5-C5H5)-1,2-FeCB9H10-, and 2,3-(η5-C5H5)2-2,31-Co2CB9H10- carboranes. The 4-CB8H14 compound was dehydrogenated at 623 K to give 4-(7)-CB8H12 carborane. Base degradation of 6-N(CH3)3-6-CB9H11 in methanol resulted in the formation of 3,4-μ-N(CH3)3CH-B5H10. The structure of all compounds was proposed on the basis of their 11B and 1H NMR spectra and X-ray diffraction was used in the case of the transition metal complexes.

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Preparation of (20E)-21-Ethoxycarbonyl-14β,17α-pregna-5,20-dien-3β-yl Hydrogen Butanedioate

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19950715 ◽

1995 ◽

Vol 60 (4) ◽

pp. 715-718 ◽

Cited By ~ 1

Author(s):

Vladimír Pouzar ◽

Ivan Černý

Keyword(s):

Title Compound ◽

Nmr Spectra ◽

Total Yield ◽

Reaction Sequence ◽

Pregnane Series ◽

H Nmr

The title compound X was prepared according to the recently published procedure for preparation of analogous derivatives in the 5β-pregnane series, using the reaction sequence I -> II -> III -> IV -> V -> VI -> VII -> VII -> IX -> X (total yield 18%). The configuration at ring D centers (14β,17α) follows from the structure of the starting ketone I and was also checked by comparing diol IV with the sample prepared by an independent route. The epimeric purity at C-17 was carefully monitored during the whole synthesis by 1H NMR spectra (singlet of 18-H3).

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